Trek rail rear shock upgrade ideas please

[Ajrail9.7]

How does it work? Much difference over the stock one? Thanks

To me night and day. It just supple and after 5 hours ride my butt is not sore like I ride the stock shock.

 

[Black8917]

Putting all the info I found in one post.

Trek rail 9.8 2021 Large Came stock with trunion rockshox shock which started leaking in a week.

Installed fox dhx2 230x65. Cannot run in low setting seat post hits. Reservoir clears in both settings.


bolts are 1mm shorter than shock + spacers
Fox mounting hardware. Upper shock bolt is 54mm shock width + 2x8mm spacer plus linkage = 70mm but 69mm bolt


Bolts


TR540755

TR599900

hardware
• Upper: 10mm x 54mm 803-03-311
• Lower: 10mm x 40mm 803-03-329

 

[Asnowmobiler]

I picked up a used dhx2 and think I need some mounting bushing. I thought I read that the ones from my rock shox just needed to be pressed out and installed into the fox shock but the center part of the bushings is way too larg.

 

[BiGJZ74]

I picked up a used dhx2 and think I need some mounting bushing. I thought I read that the ones from my rock shox just needed to be pressed out and installed into the fox shock but the center part of the bushings is way too larg.

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You haven't installed the DU bushing from the RS yet......Remove the 2 black sleeves, press out the long pin, then you need a bushing tool to press out the DU bushing from the RS shock. this is what they look like.

 

[Asnowmobiler]

The outer part of the black sleeve fits perfectly into the fox shock, so I'm thinking it's going to be loose if I just use the DU bushing. In the one picture, I inserted the black portion into the fox. Does something else go on the fox shocks along besides the DU and the mounting shaft?
The center part of the black sleeve is stepped up and larger.

 

[Doomanic]

You need DU bushings with an ID to match the steel shaft and an OD to match the shock eyelet.

 

[Asnowmobiler]

That's what it looks like, I was hoping I was wrong.
Where the heck do I buy them?

 

[Doomanic]

Good question. I couldn't find any with a quick google. I would suggest contacting the seller of the shock.

 

[Asnowmobiler]

Bought used.
Got what I hope ends up being a good deal.

 

[BiGJZ74]

The outer part of the black sleeve fits perfectly into the fox shock, so I'm thinking it's going to be loose if I just use the DU bushing. In the one picture, I inserted the black portion into the fox. Does something else go on the fox shocks along besides the DU and the mounting shaft?
The center part of the black sleeve is stepped up and larger.

I have the exact same shock….. and reused my hardware. Fox shoxs have the same ID as rock shox.

 

[Asnowmobiler]

I think our bikes came with different shocks, maybe that’s the issue. Select + on mine. I’ll press it out and give it a try but it looks too big.

 

[BiGJZ74]

I removed the upper mount of my shock for you…I’ve never heard of making different ID shocks of the same size so if it’s is different….it’s either counterfeit or drilled out, but my guess is it’s the same.

black sleeve reversed:

Black sleeve partially removed:

 

[BiGJZ74]

I think our bikes came with different shocks, maybe that’s the issue. Select + on mine. I’ll press it out and give it a try but it looks too big.

I have a rail 7, had the same crappy select +

 

[BiGJZ74]

I think our bikes came with different shocks, maybe that’s the issue. Select + on mine. I’ll press it out and give it a try but it looks too big.

Can get new hardware here

Shock Bushings | Trek Rail

 

[BiGJZ74]

Putting all the info I found in one post.

Trek rail 9.8 2021 Large Came stock with trunion rockshox shock which started leaking in a week.

Installed fox dhx2 230x65. Cannot run in low setting seat post hits. Reservoir clears in both settings.


bolts are 1mm shorter than shock + spacers
Fox mounting hardware. Upper shock bolt is 54mm shock width + 2x8mm spacer plus linkage = 70mm but 69mm bolt


Bolts


TR540755

TR599900

hardware
• Upper: 10mm x 54mm 803-03-311
• Lower: 10mm x 40mm 803-03-329

View attachment 66994

View attachment 66995

View attachment 66996

View attachment 66997

View attachment 66998

View attachment 66999

At full stroke how much travel do you think was left after seat stay contacted the seat tube? Do you think 62.5mm would clear?

 

[Asnowmobiler]

Oh crap, now I see what you’re saying. I thought that thicker part went all the way trough. Now I see, it3 parts.

 

[Asnowmobiler]

I have the mounts swapped over
thank you for all your help, it was priceless.

 

[Asnowmobiler]

Water bottle will not seat into the mount completely. I’ll see tomorrow how it works out.
9.7 Medium

 

[BiGJZ74]

Use a B-Rad 2 adapter to slide bottle up a bit. B-RAD Mounting Bases

 

[PetrD]

The Specialized bottle holder with integrated tools used with original bottle is good solution. It has enough room for dhx2 (2022).

 

[Asnowmobiler]

Not much room on the top and hitting the can on the bottom before it’s all the way in.
Med. Rail 9.7

 

[Doomanic]

hitting the can on the bottom before it’s all the way in.
Med. Rail 9.7

That's a known issue with the smaller frames.

Ohlins TTX, DVO Jade X have different orientation reservoirs so don't hit.
Some shocks have shorter reservoirs, modified EXT Storia, 2022 Fox, so may be OK.

 

[Jpzeroday]

So I am trying to figure out what the consensus is on replacing stock shocks…

What is Goldilocks for aggressive rides and long missions?

I find the RS thrushaft to be really poor…as a pedaling platform…the damping is mediocre…etc.

But what gets this bike up to its full potential? X2 or a Coil?

And does increased travel make this a better bike on big hits and drops?

(The subpar Rail suspension really has me considering moving to a Levo3, but I love the CX4 motor…it is more capable than the Brose 2.2 which I have about 100 miles on demo. If I could get the suspension dialed, I would likely stick with the rail…getting some additional travel would be a huge plus, too).

I have a Large Rail 9.9.

 

[Black8917]

I love my 165mm dhx2 with 180mm zeb ultimate smash pot. So much better than stock. All I ride is DH PNW

 

[Stray cat]

Has anyone tried to set up new Fox DHX coil shock? Piggyback looks like bigger than Fox DHX2

 

[Nuckingfuts]

After trying to make a Rockshox Super Deluxe coil work with no luck, I ended up going with a Fox X2 and am super happy. Super plush and a ton of adjustment. Fox 38 or 2:1 Charger up front next.

 

[Zorg]

After trying to make a Rockshox Super Deluxe coil work with no luck, I ended up going with a Fox X2 and am super happy. Super plush and a ton of adjustment. Fox 38 or 2:1 Charger up front next.

View attachment 73983

Hi,

Off topic , but what type and size are those rotors ?

Thanks

 

[Nuckingfuts]

Hi,

Off topic , but what type and size are those rotors ?

Thanks

those are the stock Shimano RT76, 203mm

 

[Zorg]

203 front , not 220 ? I thought all rail , or at least 7 and up, come with 220 front rotor.
So 203 are enough as of trek. That’s nice to know

 

[Nuckingfuts]

203 front , not 220 ? I thought all rail , or at least 7 and up, come with 220 front rotor.
So 203 are enough as of trek. That’s nice to know

Good question, I just pulled specs from Treks website.
I’ll measure later.